Gamereactor is an international online network covering video games on consoles, PC and mobile. It was started in Denmark in 1998 by Morten Reichel and Claus Reichel (Magazine and Online) - during the early years under the name Gamez.dk. The Magazine and Online site Gamez.dk took over the online sites Gamereactor.dk/.se/.no from Egmont Digital in 2002. Egmont started the sites in 1998. In 2001 they released Gamereactor Magazine in Norway and soon after in Sweden. Since late 2007 Gamereactor has also been available in Finland, and it also launched in Germany (Online only) in 2009. In 2010 they launched in Italy (Online only), and a Portuguese version came online in 2013. Gamereactor later opened outlets in France in November 2016, The Netherlands in January 2017, and China in January 2018.

On 1 September 2008, Gamereactor launched an English edition of the website and the magazine (PDF). Gamereactor International features news, previews and reviews, with a special interest in the Nordic gaming industry, as well as video content from GRTV. The print magazine launched in the UK in 2013, and in 2017 Gamereactor launched a cross-network English language esports sub-site covering competitive gaming.

Smartphone Apps are available on both iPhone and Android platforms, and there is a Gamereactor app on both PlayStation 4 and Xbox One. GRTV also is available as a Smart TV app for Samsung's Smart TV Hub platform.

In 2004 Gamereactor Art Director Petter Hegevall was nominated in one of the biggest Swedish Design Awards. In 2013 Gamereactor Magazine (UK) was nominated in the best Print Magazine category at the Games Media Awards, and in 2015 the team were nominated in the Best Editorial Team (Print) category.